The Drug Abuse Research Center has continued: 1) to provide a formal structure designed to encourage the cooperation of basic research scientists and clinical researchers in problem-oriented research, 2) to encourage communication among basic research scientists working in related fields, 3) to promote the development and/or expansion of certain key areas in drug abuse research, and 4) to provide an interdisciplinary educational environment for students and faculty interested in various areas of drug abuse research. The philosophy of the Research Center is that drug abuse is a complex problem which needs to be studied on a variety of levels ranging from a drug's sub-cellular actions through its sociological impact. It is impossible for any single department, let alone an isolated individual, to possess the expertise to study drugs at all these levels. The Research Center has been to provide a formal structure for encouraging interaction between scientists and clinicians from several academic departments, all of whom are working in areas related to drug abuse. Current research includes: studies of drug self-administration in infra-human primates as well as man; studies of the sensitivity of current and former methadone dependent humans to alcohol and amphetamines; neurochemical studies of drugs of abuse; metabolism of drugs of abuse in animals and man.